Exploring the influence of iron doping on structural, morphological and optical properties of chemical bath deposited cadmium selenide thin films for optoelectronic applications.

This research investigates the structural, morphological, and optical properties of Cadmium Selenide (CdSe) thin films deposited via the Chemical Bath Deposition (CBD) Technique, focusing on the impact of Iron (Fe) doping. Using Cadmium Chloride (CdCl2) and Ferrous chloride (FeCl2) as precursor materials, the research investigates how Fe doping affects the structural and photoelectric characteristics of the films. Employing various characterization methods including X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), and UV-Vis NIR spectroscopy, the study provides a comprehensive analysis of the films. XRD analysis confirms the formation of a cubic structure with a predominant orientation along the (111) plane, consistent with XRD peaks. Additionally, XRD data reveals the degradation of thin films post-annealing. Crystalline size and strain are determined using the Debye-Scherrer and Wilson formulae, while lattice constant and Size-strain plots are derived from X-ray line broadening. The average crystallite size ranges from 12 to 21 nm. Optical band gaps are found to be 2.25 eV, 2.91 eV, 2.87 eV, and 2.85 eV for the samples. Interestingly, a decrease in crystal size with increasing doping concentration correlates with a reduction in bandgap. This investigation offers valuable insights into the fabrication and characterization of CdSe thin films, particularly highlighting the impact of Fe doping on their structural and optical properties. Overall, this study provides valuable insights into the fabrication and characterization of CdSe thin films, emphasizing the importance of precise doping control for tailoring material properties and advancing their applications in photovoltaic and optoelectronic devices.

Assessing Spectral Analysis of Phytoconstituents and Their In Silico Interactions with Target Proteins in Plant Seed Extracts.

The pharmacological and preventive attributes of extracts from vegetable seeds have garnered widespread recognition within the scientific community. This study systematically assessed the in vitro antibacterial, antioxidant, and anti-breast cancer properties of phytochemicals present in various solvent-based vegetable seed extracts. We also conducted molecular docking simulations to ascertain their interactions with specific target proteins. Besides, nine distinct chemical constituents were identified using gas chromatography-mass spectrometry (GCMS). Remarkably, the ethyl acetate extract exhibited robust inhibitory effects against Gram-positive and Gram-negative bacterial strains. Furthermore, its capacity for 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging was found to be noteworthy, with an IC50 value of 550.82 ± 1.7 µg/mL, representing a scavenging efficiency of 64.1 ± 2.8%. Additionally, the ethyl acetate extract demonstrated significant hydrogen peroxide (H2O2) scavenging activity, with a maximal scavenging rate of 44.1 ± 1.70% (IC50) at a concentration of 761.17 ± 1.8 µg/mL. Intriguingly, in vitro cytotoxicity assays against human breast cancer (MCF-7) cells revealed varying levels of cell viability at different extract concentrations, suggesting potential anticancer properties. Importantly, these ethyl acetate extracts did not display toxicity to L929 cells across the concentration range tested. Subsequently, we conducted in-silico molecular docking experiments utilizing Discovery Studio 4.0 against the c-Met kinase protein (hepatocyte growth factor; PDB ID: 1N0W). Among the various compounds assessed, 3,4-Dihydroxy-1,6-bis-(3-methoxy-phenyl)-hexa-2,4-diene-1,6-dione exhibited a notable binding energy of -9.1 kcal/mol, warranting further investigation into its potential anticancer properties, clinical applications, and broader pharmacological characteristics.

Innovative Preparation of Cellulose-Mediated Silver Nanoparticles for Multipurpose Applications: Experiment and Molecular Docking Studies.

In recent years, inorganic metal nanoparticle fabrication by extraction of a different part of the plant has been gaining more importance. In this research, cellulose-mediated Ag nanoparticles (cellulose/Ag NPs) with excellent antibacterial and antioxidant properties and photocatalytic activity have been synthesized by the microwave-assisted hydrothermal method. This method is a green, simple, and low-cost method that does not use any other capping or reducing agents. X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission scanning microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), and UV-visible spectroscopic techniques were used to investigate the structure, morphology, as well as components of the generated cellulose/Ag NPs. In fact, XRD results confirm the formation of the face-centered cubic phase of Ag nanoparticles, while the FTIR spectra showed that the synergy of carbohydrates and proteins is responsible for the formation of cellulose/Ag NPs by the green method. It was found that the green-synthesized silver nanoparticles showed good crystallinity and a size range of about 20-30 nm. The morphology results showed that cellulose has a cavity-like structure and the green-synthesized Ag NPs were dispersed throughout the cellulose polymer matrix. In comparison to cellulose/Ag NPs and Ag nanoparticles, cellulose/Ag NPs demonstrated excellent antibacterial activity, Proteus mirabilis (MTCC 1771) possessed a maximum inhibition zone of 18.81.5 mm at 2.5 g/mL, and Staphylococcus aureus (MTTC 3615) had a minimum inhibition zone of 11.30.5 mm at 0.5 g/mL. Furthermore, cellulose/Ag NPs also exhibited a significant radical scavenging property against the DDPH free radical, and there was a higher degradation efficiency compared to pure Ag NPs against Rhodamine B as 97.38% removal was achieved. Notably, cellulose/Ag NPs remarkably promoted the transfer and separation of photogenerated electron-hole (e-/h+) pairs, thereby offering prospective application of the photodegradation efficiency for Rhodamine B (RhB) as well as antibacterial applications. With the findings from this study, we could develop efficient and environmentally friendly cellulose/Ag nanoparticles using low-cost, environmentally friendly materials, making them suitable for industrial and technological applications.

MASP2 levels are elevated in thrombotic microangiopathies: association with microvascular endothelial cell injury and suppression by anti-MASP2 antibody narsoplimab.

Involvement of the alternative complement pathway (AP) in microvascular endothelial cell (MVEC) injury characteristic of a thrombotic microangiopathy (TMA) is well documented. However, the role of the lectin pathway (LP) of complement has not been explored. We examined mannose-binding lectin associated serine protease (MASP2), the effector enzyme of the LP, in thrombotic thrombocytopenic purpura, atypical hemolytic uremic syndrome and post-allogeneic hematopoietic stem cell transplantation (alloHSCT) TMAs. Plasma MASP2 and terminal complement component sC5b-9 levels were assessed by enzyme-linked immunosorbent assay (ELISA). Human MVEC were exposed to patient plasmas, and the effect of the anti-MASP2 human monoclonal antibody narsoplimab on plasma-induced MVEC activation was assessed by caspase 8 activity. MASP2 levels were highly elevated in all TMA patients versus controls. The relatively lower MASP2 levels in alloHSCT patients with TMAs compared to levels in alloHSCT patients who did not develop a TMA, and a significant decrease in variance of MASP2 levels in the former, may reflect MASP2 consumption at sites of disease activity. Plasmas from 14 of the 22 TMA patients tested (64%) induced significant MVEC caspase 8 activation. This was suppressed by clinically relevant levels of narsoplimab (1·2 µg/ml) for all 14 patients, with a mean 65·7% inhibition (36.8-99.4%; P < 0·0001). In conclusion, the LP of complement is activated in TMAs of diverse etiology. Inhibition of MASP2 reduces TMA plasma-mediated MVEC injury in vitro. LP inhibition therefore may be of therapeutic benefit in these disorders.

A study on agricultural drought vulnerability at disaggregated level in a highly irrigated and intensely cropped state of India.

Drought is an important global hazard, challenging the sustainable agriculture and food security of nations. Measuring agricultural drought vulnerability is a prerequisite for targeting interventions to improve and sustain the agricultural performance of both irrigated and rain-fed agriculture. In this study, crop-generic agricultural drought vulnerability status is empirically measured through a composite index approach. The study area is Haryana state, India, a prime agriculture state of the country, characterised with low rainfall, high irrigation support and stable cropping pattern. By analysing the multiyear rainfall and crop condition data of kharif crop season (June-October) derived from satellite data and soil water holding capacity and groundwater quality, nine contributing indicators were generated for 120 blocks (sub-district administrative units). Composite indices for exposure, sensitivity and adaptive capacity components were generated after assigning variance-based weightages to the respective input indicators. Agricultural Drought Vulnerability Index (ADVI) was developed through a linear combination of the three component indices. ADVI-based vulnerability categorisation revealed that 51 blocks are with vulnerable to very highly vulnerable status. These blocks are located in the southern and western parts of the state, where groundwater quality is saline and water holding capacity of soils is less. The ADVI map has effectively captured the spatial pattern of agricultural drought vulnerability in the state. Districts with large number of vulnerable blocks showed considerably larger variability of de-trended crop yields. Correlation analysis reveals that crop condition variability, groundwater quality and soil factors are closely associated with ADVI. The vulnerability index is useful to prioritise the blocks for implementation of long-term drought management plans. There is scope for improving the methodology by adding/fine-tuning the indicators and by optimising the weights.

Costimulatory role of CXCR4 with pre-TCR and its crosstalk with PI3K in beta-selection of thymocytes.

Chemokines were initially thought of only as regulators of the migration of developing thymocytes between different compartments of the thymus and were predicted also to be involved in early stages of thymocyte development. Recent data have suggested additional functions for the chemokine receptor CXCR4-a G protein-coupled receptor-in thymocyte development, particularly during the beta-selection developmental checkpoint. Phosphotidylinositol 3-kinase interacts with the pre-T cell receptor and CXCR4 during migration, proliferation, and differentiation of developing thymocytes. CXCR4 and Notch signaling, along with inhibition of glycogen synthase kinase-3beta (GSK-3beta), are essential for the proliferation and differentiation of thymocytes during beta-selection. Thus, a critical role of chemokines and its downstream signaling in the beta-selection of thymocytes has been demonstrated.

Mammographic features of isolated tuberculous mastitis.

OBJECTIVE: To present the mammography findings in 8 patients with tuberculosis (TB) of the breast, with a review of the literature. METHODS: This study is a retrospective data collection. Each chart with confirmed breast TB based on bacteriology or pathologic findings was analyzed for clinical presentation, gender, nationality, demographic data, prior history of TB, investigation, management, mammographic findings and ultrasound, when available. Mammograms were reviewed by 2 consultant radiologists without knowing the previous diagnosis or the nature of the study. The study was carried out at The State Tuberculosis Registry and Radiology Department, Hamad General Hospital, State of Qatar, from 1990 to 2002. RESULTS: Out of 13 females with TB mastitis, only 8 cases had mammograms preoperatively. The incidence of breast TB in Qatar is rare (1/1000 mammograms per year). Three types of TB mastitis were identified in our study; the nodular (50%), the diffuse (37.5%) of which 77% were limited to one sector of the breast and the sclerosing (12.5%) mastitis. Three patients (43%) were reported as carcinoma. CONCLUSION: Although mammography identified 3 types of TB, it was not helpful in differentiating TB from carcinoma of the breast. However, the careful evaluation of the degree of density and trabecular thickening of the mass in relation to it size might reduce the number of false positive cases of carcinoma diagnosed with mammograms. Biopsy specimen remains the best diagnostic tool in TB mastitis.

Cutting edge: Differential regulation of chemoattractant receptor-induced degranulation and chemokine production by receptor phosphorylation.

Phosphorylation of G protein-coupled receptors and the subsequent recruitment of beta-arrestin play an important role in desensitization of receptor-mediated responses, including degranulation in leukocytes. In this study, we report that receptor phosphorylation also provides a stimulatory signal for CCR ligand 2 (CCL2) production. C3a stimulated degranulation in a basophilic leukemia RBL-2H3 cell expressing wild-type C3aR or a phosphorylation-deficient mutant (DeltaST-C3aR). In contrast, C3a caused CCL2 production only in C3aR but not DeltaST-C3aR cells. Furthermore, overexpression of G protein-coupled receptor kinase 2 resulted in enhancement of both ligand-induced receptor phosphorylation and CCL2 production but inhibition of degranulation. Agonist activation of C3aR, but not DeltaST-C3aR, led to the translocation of green fluorescent protein tagged beta-arrestin 2 from the cytoplasm to the plasma membrane. These data demonstrate that receptor phosphorylation, which provides a turn off signal for degranulation, is essential for CCL2 production.

Chemokine production by G protein-coupled receptor activation in a human mast cell line: roles of extracellular signal-regulated kinase and NFAT.

Chemoattractants are thought to be the first mediators generated at sites of bacterial infection. We hypothesized that signaling through G protein-coupled chemoattractant receptors may stimulate cytokine production. To test this hypothesis, a human mast cell line (HMC-1) that normally expresses receptors for complement components C3a and C5a at low levels was stably transfected to express physiologic levels of fMLP receptors. We found that fMLP, but not C3a or C5a, induced macrophage inflammatory protein (MIP)-1ss (CCL4) and monocyte chemoattractant protein-1 (CCL2) mRNA and protein. Although fMLP stimulated both sustained Ca(2+) mobilization and phosphorylation of extracellular signal-regulated kinase (ERK), these responses to C3a or C5a were transient. However, transient expression of C3a receptors in HMC-1 cells rendered the cells responsive to C3a for sustained Ca(2+) mobilization and MIP-1ss production. The fMLP-induced chemokine production was blocked by pertussis toxin, PD98059, and cyclosporin A, which respectively inhibit G(i)alpha activation, mitgen-activated protein kinase kinase-mediated ERK phosphorylation, and calcineurin-mediated activation of NFAT. Furthermore, fMLP, but not C5a, stimulated NFAT activation in HMC-1 cells. These data indicate that chemoattractant receptors induce chemokine production in HMC-1 cells with a selectivity that depends on the level of receptor expression, the length of their signaling time, and the synergistic interaction of multiple signaling pathways, including extracellular signal-regulated kinase phosphorylation, sustained Ca(2+) mobilization and NFAT activation.

Caged chemotactic peptides.

This work has as its ultimate goal the creation of a concentration spike of a chemoattractant peptide in a time-resolved and spatially defined way using a light pulse. This strategy requires "caging" the peptide with a photochemically removable group. Model studies used alanine ethyl ester in reductive amination with nitrobenzaldehydes to form two different N-nitrobenzyl derivatives. An fMLF peptide bearing these two N-terminal nitrobenzyl groups was also prepared. The yield and kinetics of their deprotection to return the fMLF peptide were determined. It was established that the caged peptides have vastly reduced biological activity as chemoattractants, as designed.

Characterization of derivatives of the high-molecular-mass penicillin-binding protein (PBP) 1 of Mycobacterium leprae.

Mycobacterium leprae has two high-molecular-mass multimodular penicillin-binding proteins (PBPs) of class A, termed PBP1 and PBP1* [Lepage, Dubois, Ghosh, Joris, Mahapatra, Kundu, Basu, Chakrabarti, Cole, Nguyen-Disteche and Ghuysen (1997) J. Bacteriol. 179, 4627-4630]. PBP1-Xaa-beta-lactamase fusions generated periplasmic beta-lactamase activity when Xaa (the amino acid of PBP1 at the fusion junction) was residue 314, 363, 407, 450 or 480. Truncation of the N-terminal part of the protein up to residue Leu-147 generated a penicillin-binding polypeptide which could still associate with the plasma membrane, whereas [DeltaM1-R314]PBP1 (PBP1 lacking residues Met-1 to Arg-314) failed to associate with the membrane, suggesting that the region between residues Leu-147 and Arg-314 harbours an additional plasma membrane association site for PBP1. Truncation of the C-terminus up to 42 residues downstream of the KTG (Lys-Thr-Gly) motif also generated a polypeptide that retained penicillin-binding activity. [DeltaM1-R314]PBP1 could be extracted from inclusion bodies and refolded under appropriate conditions to give a form capable of binding penicillin with the same efficiency as full-length PBP1. This is, to the best of our knowledge, the first report of a soluble derivative of a penicillin-resistant high-molecular-mass PBP of class A that is capable of binding penicillin. A chimaeric PBP in which the penicillin-binding (PB) module of PBP1 was fused at its N-terminal end with the non-penicillin-binding (n-PB) module of PBP1* retained pencillin-binding activity similar to that of PBP1, corroborating the finding that the n-PB module of PBP1 is dispensable for its penicillin-binding activity.

Molecular characterization of the SHV-11 beta-lactamase of Shigella dysenteriae.

A beta-lactamase with an M(r) of 29,000 and a pI of 7.6 was partially purified from a clinical isolate of Shigella dysenteriae. The bla gene encoded the SHV-11 enzyme carrying the substitution Leu-->Gln at position 35 and was linked to a strong promoter. This variant, unlike the prototype SHV-1 enzyme, hydrolyzed oxacillin, cloxacillin, and oxyiminocephalosporins such as cefotaxime.

Involvement of an efflux system in high-level fluoroquinolone resistance of Shigella dysenteriae.

Shigella dysenteriae represent one of the growing list of antibiotic-resistant bacteria. Quinolones are widely employed to treat shigellosis. However, quinolone resistance has already been reported, necessitating an understanding of the mechanisms of development of resistance. We demonstrate that high-level fluoroquinolone resistance of S. dysenteriae exposed to these antibiotics may occur in the absence of gyrA mutations and involve a proton motive force(pmf)-dependent efflux system.

Involvement of a 43-kilodalton outer membrane protein in beta-lactam resistance of Shigella dysenteriae.

A beta-lactam-sensitive strain (C152) of Shigella dysenteriae showed two major outer membrane proteins (OMPs) with M(r)s of 43,000 and 38,000, while the clinical isolate M2 lacked the 43,000-Mr OMP, which acted as a channel for beta-lactam antibiotics. Permeability of beta-lactams across the outer membrane (OM) of M2 was lower than that across the OM of C152. Mutants deficient in the 43-kDa OMP could be selected in vitro from strain C152 in the presence of cefoxitin. All beta-lactam-resistant strains were sensitive to imipenem.